A train consist is a group of rail vehicles that make up a train. In most consists, the group of rail vehicles includes at least one locomotive (often more than one), one or more freight or passenger vehicles, and, in some applications, a caboose. The locomotive(s), although generally located at the leading end of the consist, can alternatively be located at any other position along its length. A locomotive provides power to the rest of the consist, and the lead locomotive generates operator- and/or autonomous control commands directed to components of the locomotive and to other vehicles in the consist (e.g., traction commands, braking commands, destination commands, etc.). The caboose, if present, is generally located at the trailing end of the consist. In some embodiments, control commands can also or alternatively be generated by an End of Train (EOT) unit at the rear of the train and directed to one or more other vehicles in the consist. EOT monitoring systems perform two basic functions. In the first of these functions, the EOT unit monitors brake pipe pressure, motion, and other parameters, and communicates the information via a radio transceiver to a Locomotive Cab Unit (LCU). In a second function, the EOT unit allows an operator to initiate an emergency brake application from the LCU to the EOT unit via the radio link. This provides a means of rapidly exhausting the brake pipe from the rear of the train, supplementing normal emergency braking initiated from the front end of the train.
Communication within a train consist can involve a range of technologies. For example, power between vehicles can be transmitted via hard-wired pinned connections. Control commands such as the commands sent from the LCU to the EOT unit can be facilitated wirelessly using radio transceivers, shortwave radio, and other known technologies. Other ways of communicating power, control commands, and data between vehicles have also been utilized. Although functional, each of the communication technologies described above may have drawbacks. For example, it may be possible for hard-wired pinned connections to be insufficiently coupled or coupled incorrectly, and/or for components of the connections to fail during use (e.g., pins in the connection can break). Wireless communication can be insecure and prone to interference from outside sources. These difficulties increase as a size of the consist increases, while at the same time, the importance of accurate and reliable communication also increases.
One attempt to provide an additional pressure monitoring function for an EOT monitoring system to enable an integrity check of the train is disclosed in U.S. Pat. No. 5,507,457 that issued to Kull on Apr. 16, 1996 (“the '457 patent”). In particular, the '457 patent discloses providing a pressure input capability and software to the LCU microprocessor that allows continuity of the brake pipe of a train to be verified. A pressure sensor is installed in the LCU to sense brake application. A drop in pressure at the EOT unit is expected when a brake application is initiated from the LCU. If a pressure drop is not sensed at the EOT unit within a predetermined period of time, it is assumed to be due to either a corrupted brake pipe or a communications failure between the LCU and EOT unit. The microprocessor in the LCU will then initiate a communications check by interrogating the EOT unit and issuing an alarm if no reply is received.
Although the system of the '457 patent may have provided additional checks on brake pipe integrity for a train, the system may still be problematic. In particular, the system of the '457 patent still relies on wireless communication along the consist, with the inherent difficulties this may present. In addition, the system of the '457 patent only monitors an overall drop in pressure for the entire length of the train between the LCU and the EOT unit. The system does not provide any way of determining where along the train a possible fault may be occurring.
The vehicle coupling fault detecting system of the present disclosure solves one or more of the problems set forth above and/or other problems in the art.